Raman spectroscopy investigation of various saturated monoacid triglycerides

A study of the vibrational behavior of five saturated monoacid triacylglycerides is performed by Raman spectroscopy at room temperature in the 3100-500 cm(-1) spectral range. The splitting of the C=O stretching mode leads to conclude on the existence of two or three geometries of C=O in the "knot" group O-C=O. The C=O stretching mode seems to be a good tool for distinguishing the polymorphic forms of the studied triglycerides. The assignments of the different C=H stretching modes are performed in the 1500-500 cm(-1) spectral range. The 1(2845)/1(2880) (in the C-H stretching spectral region) and 1(1445)/1(1296) intensity ratios (between the maximal intensity 1(1445) of the CH2 scissoring mode and the maximal intensity 1(] 296) of the skeletal vibration of -(CH2)(n)-in-phase twist) seem to depend on the type of polymorphic forms of these molecules. (c) 2005 Elsevier Ireland Ltd. All rights reserved.